CVE-2021-20372Network attack vector

Authenticated service interruption via insufficient permission checks

Published Oct 7, 2021 · Updated Sep 16, 2024

Access-control failure in IBM Sterling File Gateway allows remote authenticated users to interrupt another user's service. IBM identifies insufficient permission checking in the user interface but has not published the affected request, function, or incorrect authorization decision. A valid account is required; affected branches are 2.2.0.0 through 5.2.6.5_3, 6.0.0.0 through 6.0.0.6, 6.0.1.0 through 6.0.3.4, and 6.1.0.0 through 6.1.0.1.

CVSS severity4.3
Medium
EPSS probability1.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Access-control failure in IBM Sterling File Gateway allows remote authenticated users to interrupt another user's service. IBM identifies insufficient permission checking in the user interface but has not published the affected request, function, or incorrect authorization decision. A valid account is required; affected branches are 2.2.0.0 through 5.2.6.5_3, 6.0.0.0 through 6.0.0.6, 6.0.1.0 through 6.0.3.4, and 6.1.0.0 through 6.1.0.1.

The record

CVE
CVE-2021-20372
Published
Oct 7, 2021
Updated
Sep 16, 2024
Vendor
IBM
Product
IBM Sterling File Gateway
Classifications
T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.2.0.0
  2. Affected versionversion=5.2.6.5_3
  3. Affected versionversion=6.0.0.0
  4. Affected versionversion=6.0.0.6
  5. Affected versionversion=6.0.1.0
  6. Affected versionversion=6.0.3.4
  7. Affected versionversion=6.1.0.0
  8. Affected versionversion=6.1.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · IBM Sterling File Gatewayversion=2.2.0.0; version=5.2.6.5_3; version=6.0.0.0; version=6.0.0.6; version=6.0.1.0; version=6.0.3.4; version=6.1.0.0; version=6.1.0.1

Published CVSS scores

4.3IBM CorporationCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:N/A:P
4.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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